This invention relates generally to infusion therapy and IV injection or sampling sites, and more particularly to apparatus for and method of making an injection or sampling site, such as an IV injection site, adapted for use with a blunt cannula.
In an effort to reduce the risk of transmitting infectious diseases, such as hepatitis and AIDS, via accidental needle sticks, various designs of IV injection sites have been developed that are adapted to receive a blunt cannula and/or shielded cannula. See, e.g., Special Report and Product Review, Needlestick-Prevention Devices, Health Devices, pages 154-180 (ECRI, Plymouth Meeting, Penn. 1991). One approach has been to employ a slit septum Y-site in which a slit elastomeric septum is compressed in the Y-site housing. A blunt cannula can be introduced through the slit of the septum, and assuming the design works as intended, the septum will seal against the cannula shaft. When the cannula is removed, the septum seals itself.
Injection sites of this type are either available from or publicized by Baxter International, Inc., Deerfield, Ill., under the trade designation "Baxter's Needle-Less Injection Sites"; Abbott Laboratories, Inc., Abbott Park, Ill., under the trade designation "LifeShield Infection Control System"; and Kendall McGaw Laboratories, Inc., Irvine, Calif., under the trade designation "SafeLine No-Needle I.V. System". A blunt cannula has been available from Becton, Dickinson and Company, Paramus, N.J., under the trade designation "Interlink System".
One problem with these systems is that they are sometimes incompatible. Some slit septum systems have permitted leakage either when a cannula is inserted or when no cannula has been inserted. In at least one slit septum site, it is possible to upset the septum in its housing by using an unspecified cannula or attempting to insert the cannula through the material of the septum somewhere other than through the slit.
Another problem with slit septum systems is inconsistent resistance to being pierced with a blunt cannula. Injection sites of the same system will require the medical practitioner to exert widely varying amount of force before the blunt cannula will pierce the septum.